Tuesday, May 26, 2015

A Eureka Moment

Thanks to a Facebook contributor, it appears I now have the solution to Glinda’s poor running and horrible gas mileage.

A little background. Back when I sent the original '68 carburetors down to a carb guru to have the jets relocated for racing, he discovered that he could not modify them because of all the smog changes GM made. He, instead, traded me some '66 carb bases with the modifications. He sent them back to me without any of the interior parts since that was the way he’d received the ‘68s. I rebuilt the bases using the ’68 parts.

Sadly for me, there’s an important difference between the '65-’67 and the ’68s I’d disassembled. GM put a small needle valve in bottom of the carb base that I did not know about (not in earlier or later carbs). Without this valve, fuel runs too freely into the well that feeds the venture, thus the 14 MPG. Running way too rich had fouled the plugs with soot, explaining why, with the near-flooding, performance was so poor. A phone call to Jeff at the Corvair Ranch, and a couple GUP needles are on their way to me.

Prior to this discovery, I’d thought there had to be a leak in one of the fuel lines – probably the pressurized return line. That belief prompted me to put Glinda up in the air so I could remove the tunnel covers and inspect everything from the bottom-side. Everything was dry even with the engine running. While I was lying on the ground revving the engine, I could easily see the black smoke associated with an engine running rich. That’s what provoked me to take a video (click her to see, but turn down the volume), post it to Facebook, and seek the help of the Corvair community.

I also pulled the spark plugs and cleaned all the soot from them. Finally, I re-set the floats to ’66 carburetor spec values for level and drop. Once the needles are installed and the carbs are bolted back together, this engine should run like a top.

Another task I was able to get to yesterday were creating two extended J-bolts to retain the raised air cleaner. As shown below, I’ve been using zip-ties since adding the PVC spacers. Not anymore. The welder permanently joined two nuts so the stock J-bolt screws into one end and a 3 inch long piece of threaded rod goes into the other end. A nice benefit to this new setup is the J-bolt is now captured. I’ve lost at least one of the stock J-bolts after removing the air cleaner and placing it on the ground. Once loosened, the extended nut on one side and wing-nut on the other will keep the J-bolt permanently part of the air cleaner.

After cleaning the garage, I then took a few minutes to get out the buffer and see if anything could be done with Glinda’s oxidized paint. I tackled the passenger side of the hood figuring I had nothing to lose. After a few minutes of buffing, the pad had a green tint to it as it should. I then got out the Turtle Wax and applied it per the directions. The one side of the hood looks nicer, but there’s no way I’d say it’s shiny.

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